[Ocfs2-devel] vmstore option - mkfs

[Ocfs2-devel] vmstore option - mkfs

[Artur Baruchi]

Hi.

I tried to find some information about the option vmstore when
formating a device, but didnt found anything about it (no
documentation, I did some greps inside the source code, but nothing
returned). My doubts about this:

- What kind of optimization this option creates in my file system to
store vm images? I mean.. what does exactly this option do?
- Where, in source code, I can find the part that makes this optimization?

Thanks in advance.

Att.
Artur Baruchi

[Ocfs2-devel] vmstore option - mkfs

[Sunil Mushran]

fstype is a handy way to format the volume with parameters that are thought
to be useful for that use-case. The result of this is printed during format by
way of the parameters selected. man mkfs.ocfs2 has a blurb about the features
it enabled by default.

On 11/16/2011 08:45 AM, Artur Baruchi wrote:
> Hi.
>
> I tried to find some information about the option vmstore when
> formating a device, but didnt found anything about it (no
> documentation, I did some greps inside the source code, but nothing
> returned). My doubts about this:
>
> - What kind of optimization this option creates in my file system to
> store vm images? I mean.. what does exactly this option do?
> - Where, in source code, I can find the part that makes this optimization?
>
> Thanks in advance.
>
> Att.
> Artur Baruchi
>

[Ocfs2-devel] vmstore option - mkfs

[Artur Baruchi]

I just found this:

+	{OCFS2_FEATURE_COMPAT_BACKUP_SB | OCFS2_FEATURE_COMPAT_JBD2_SB,
+	 OCFS2_FEATURE_INCOMPAT_SPARSE_ALLOC |
+	 OCFS2_FEATURE_INCOMPAT_INLINE_DATA |
+	 OCFS2_FEATURE_INCOMPAT_XATTR |
+	 OCFS2_FEATURE_INCOMPAT_REFCOUNT_TREE,
+	 OCFS2_FEATURE_RO_COMPAT_UNWRITTEN},  /* FS_VMSTORE */

These options are the ones that, when choosing for vmstore, are
enabled by default. Is this correct?

Thanks.

Att.
Artur Baruchi



On Wed, Nov 16, 2011 at 3:26 PM, Sunil Mushran <sunil.mushran@oracle.com> wrote:
> fstype is a handy way to format the volume with parameters that are thought
> to be useful for that use-case. The result of this is printed during format
> by
> way of the parameters selected. man mkfs.ocfs2 has a blurb about the
> features
> it enabled by default.
>
> On 11/16/2011 08:45 AM, Artur Baruchi wrote:
>>
>> Hi.
>>
>> I tried to find some information about the option vmstore when
>> formating a device, but didnt found anything about it (no
>> documentation, I did some greps inside the source code, but nothing
>> returned). My doubts about this:
>>
>> - What kind of optimization this option creates in my file system to
>> store vm images? I mean.. what does exactly this option do?
>> - Where, in source code, I can find the part that makes this optimization?
>>
>> Thanks in advance.
>>
>> Att.
>> Artur Baruchi
>>
>
>

[Ocfs2-devel] vmstore option - mkfs

[Sunil Mushran]

Yes. But this is just the features. It also selects the appropriate cluster size, block size,
journal size, etc. All the params selected are printed by mkfs. You also have the option of
running with the --dry-option to see the params.

On 11/16/2011 09:41 AM, Artur Baruchi wrote:
> I just found this:
>
> +	{OCFS2_FEATURE_COMPAT_BACKUP_SB | OCFS2_FEATURE_COMPAT_JBD2_SB,
> +	 OCFS2_FEATURE_INCOMPAT_SPARSE_ALLOC |
> +	 OCFS2_FEATURE_INCOMPAT_INLINE_DATA |
> +	 OCFS2_FEATURE_INCOMPAT_XATTR |
> +	 OCFS2_FEATURE_INCOMPAT_REFCOUNT_TREE,
> +	 OCFS2_FEATURE_RO_COMPAT_UNWRITTEN},  /* FS_VMSTORE */
>
> These options are the ones that, when choosing for vmstore, are
> enabled by default. Is this correct?
>
> Thanks.
>
> Att.
> Artur Baruchi
>
>
>
> On Wed, Nov 16, 2011 at 3:26 PM, Sunil Mushran<sunil.mushran@oracle.com>  wrote:
>> fstype is a handy way to format the volume with parameters that are thought
>> to be useful for that use-case. The result of this is printed during format
>> by
>> way of the parameters selected. man mkfs.ocfs2 has a blurb about the
>> features
>> it enabled by default.
>>
>> On 11/16/2011 08:45 AM, Artur Baruchi wrote:
>>> Hi.
>>>
>>> I tried to find some information about the option vmstore when
>>> formating a device, but didnt found anything about it (no
>>> documentation, I did some greps inside the source code, but nothing
>>> returned). My doubts about this:
>>>
>>> - What kind of optimization this option creates in my file system to
>>> store vm images? I mean.. what does exactly this option do?
>>> - Where, in source code, I can find the part that makes this optimization?
>>>
>>> Thanks in advance.
>>>
>>> Att.
>>> Artur Baruchi
>>>
>>

[Ocfs2-devel] vmstore option - mkfs

[Artur Baruchi]

That's fine...

Using vmstore:
vegeta:~ # mkfs.ocfs2 -T vmstore -n /dev/drbd1
mkfs.ocfs2 1.4.3
Dry run
Filesystem Type of vmstore
Label:
Features: sparse backup-super unwritten inline-data
strict-journal-super metaecc xattr indexed-dirs refcount
Block size: 4096 (12 bits)
Cluster size: 131072 (17 bits)
Volume size: 16105472000 (122875 clusters) (3932000 blocks)
Cluster groups: 4 (tail covers 26107 clusters, rest cover 32256 clusters)
Extent allocator size: 8388608 (2 groups)
Journal size: 134217728
Node slots: 8

Default mkfs:
vegeta:~ # mkfs.ocfs2 -n /dev/drbd1
mkfs.ocfs2 1.4.3
Dry run
Label:
Features: sparse backup-super unwritten inline-data
strict-journal-super metaecc xattr indexed-dirs
Block size: 4096 (12 bits)
Cluster size: 4096 (12 bits)
Volume size: 16105598976 (3932031 clusters) (3932031 blocks)
Cluster groups: 122 (tail covers 29055 clusters, rest cover 32256 clusters)
Extent allocator size: 4194304 (1 groups)
Journal size: 100659200
Node slots: 8


Thanks for your help.

Att.
Artur Baruchi



On Wed, Nov 16, 2011 at 3:45 PM, Sunil Mushran <sunil.mushran@oracle.com> wrote:
> Yes. But this is just the features. It also selects the appropriate cluster
> size, block size,
> journal size, etc. All the params selected are printed by mkfs. You also
> have the option of
> running with the --dry-option to see the params.
>
> On 11/16/2011 09:41 AM, Artur Baruchi wrote:
>>
>> I just found this:
>>
>> + ? ? ? {OCFS2_FEATURE_COMPAT_BACKUP_SB | OCFS2_FEATURE_COMPAT_JBD2_SB,
>> + ? ? ? ?OCFS2_FEATURE_INCOMPAT_SPARSE_ALLOC |
>> + ? ? ? ?OCFS2_FEATURE_INCOMPAT_INLINE_DATA |
>> + ? ? ? ?OCFS2_FEATURE_INCOMPAT_XATTR |
>> + ? ? ? ?OCFS2_FEATURE_INCOMPAT_REFCOUNT_TREE,
>> + ? ? ? ?OCFS2_FEATURE_RO_COMPAT_UNWRITTEN}, ?/* FS_VMSTORE */
>>
>> These options are the ones that, when choosing for vmstore, are
>> enabled by default. Is this correct?
>>
>> Thanks.
>>
>> Att.
>> Artur Baruchi
>>
>>
>>
>> On Wed, Nov 16, 2011 at 3:26 PM, Sunil Mushran<sunil.mushran@oracle.com>
>> ?wrote:
>>>
>>> fstype is a handy way to format the volume with parameters that are
>>> thought
>>> to be useful for that use-case. The result of this is printed during
>>> format
>>> by
>>> way of the parameters selected. man mkfs.ocfs2 has a blurb about the
>>> features
>>> it enabled by default.
>>>
>>> On 11/16/2011 08:45 AM, Artur Baruchi wrote:
>>>>
>>>> Hi.
>>>>
>>>> I tried to find some information about the option vmstore when
>>>> formating a device, but didnt found anything about it (no
>>>> documentation, I did some greps inside the source code, but nothing
>>>> returned). My doubts about this:
>>>>
>>>> - What kind of optimization this option creates in my file system to
>>>> store vm images? I mean.. what does exactly this option do?
>>>> - Where, in source code, I can find the part that makes this
>>>> optimization?
>>>>
>>>> Thanks in advance.
>>>>
>>>> Att.
>>>> Artur Baruchi
>>>>
>>>
>
>